Expansible honeycomb-type void fillers made of a lightweight fibrous stock such as corrugated paperboard have found wide acceptance because they provide effective protection of cargo at low overall cost thereby benefitting the ultimate consumer as well as all merchandising, shipping and handling operations, back to and including the manufacturer.
In order to effectively fill void areas in cargo vehicles it is generally desirable that honeycomb-type fillers, when expanded, assume a shape as nearly rectangular as possible. A problem which has long been recognized in this connection derives from the fact that when honeycomb fillers are expanded beyond a predetermined length, the mid-portions of the sides tend to pull inwardly, imparting a waist-like or hourglass configuration to the expanded filler and creating unprotected areas. Overstretching by the workman who installs the filler in the truck, rail car or other carrier, or overstretching which occurs during use due to vibration and the effect of gravity has in the past, by causing such hourglass-type distortion, been the cause of cargo damage due to shifting and/or falling of unprotected portions of the cargo. Considerable effort has been devoted to overcoming the hourglass distortion problem. See for example Bramlett U.S. Pat. No. 3,593,671, Sewell U.S. Pat. No. 4,007,309, Sewell et al, U.S. Pat. No. 4,372,717, and the co-pending U.S. patent application of Paul A. Wnuk et al, Ser. No. 393,662, filed June 30, 1982, belonging to the owner of the present application.
Although the inventions disclosed in such previous patents and patent application reduce the tendency to hourglass distortion, some of such prior art solutions require introducing complication in the form of parts which add to the direct cost of the fillers, while all of such prior art stretch limiting techniques result in reducing the expanded length of the filler thereby making it necessary to provide additional filler material at the bottom, in order to achieve a properly rectangular configuration which will effectively fill the void space.
An important object of the present invention, therefore, is to provide an improved void filler of the honeycomb type incorporating means for increasing the effective expanded length of the filler without increasing the tendency toward hourglass distortion. A related object is to provide improved suspension means for supporting the filler in depending relation to the suspension means.
Another object of the invention is to provide a honeycomb-type filler made of corrugated paperboard having improved folding characteristics which promote ease and speed of installation.
Still another object of the invention is to provide an improved void filler of the honeycomb-type which incorporates side cell wall portions which have the dual function of resisting hourglass distortion and of preventing the fillers, when used side-by-side, from interfiting and reducing the effective protected space in the lateral dimension.
Other objects and advantages of the invention will become apparent upon consideration of the present disclosure in its entirety.